88 L98 Upshift Light on, Sputters....HELP?
Thread Starter
Instructor
Joined: Jun 2003
Posts: 126
Likes: 7
From: Markham Ontario
88 L98 Upshift Light on, Sputters....HELP?
I was crusing around on Saturday and my car sputtered and then wanted to stall... quickly hit the throttle and I was away. From that point on, the upshift light was on and a small D or O on on the tach. By the way, it's an Automatic car.
All the way home, it was sputtering, but power was there.
I am guessing the fuel pump is on its' way out. I turn the key to the on position and I am not hearing the pump cycle, like I usually do.
However, the car now starts and idles fine...no sign of the light on anymore. Suggestions?
Anyone have this problem?
Thanks
DSSKing
All the way home, it was sputtering, but power was there.
I am guessing the fuel pump is on its' way out. I turn the key to the on position and I am not hearing the pump cycle, like I usually do.
However, the car now starts and idles fine...no sign of the light on anymore. Suggestions?
Anyone have this problem?
Thanks
DSSKing
Le Mans Master
Joined: Jun 2001
Posts: 6,694
Likes: 3
From: Less Talk, More WOT | Houston TX
Hmmm, well I don't have an answer to your problem but I can tell you the function of both of those lights on your dash.
The Upshift light comes on when you leave your car in D for an extended period of time at high rpm (not sure of the speed but should be around 55mph or so) Shifting into [D] should make it go away.
The [O] as far as I know shouldn't be used in automatic cars, as it tells whether or not overdrive is engaged on the earlier 4+3 manual transmissions.
Hope this helps
The Upshift light comes on when you leave your car in D for an extended period of time at high rpm (not sure of the speed but should be around 55mph or so) Shifting into [D] should make it go away.
The [O] as far as I know shouldn't be used in automatic cars, as it tells whether or not overdrive is engaged on the earlier 4+3 manual transmissions.
Hope this helps
Thread Starter
Instructor
Joined: Jun 2003
Posts: 126
Likes: 7
From: Markham Ontario
Hmm. Hope it's not the ECM. What's one worth for my 88 L98 and where is it located in this car?
I'll take it to Redline where I have all the work done and ask them to diagnose it.
Funny that it fired up last night (it always starts after this problem) and idled for 10 minutes with no apparent problems.
Could this be bad fuel? I have a half tank of premium Shell gas in there which I never use. Hmmmm....
I'll take it to Redline where I have all the work done and ask them to diagnose it.
Funny that it fired up last night (it always starts after this problem) and idled for 10 minutes with no apparent problems.
Could this be bad fuel? I have a half tank of premium Shell gas in there which I never use. Hmmmm....
Le Mans Master
Joined: Oct 2003
Posts: 6,130
Likes: 2
From: seattle WA
Without the stutter-mine did the same thing last week. There is the upshift indicator (kinda looks like a house) and if you look real close the 0 has a D in it, meaning to shift to 4th (BTW, mines an 87 auto) or the indicator on your shift panel to the 0 with a D in it. The indicators supposedly come on for fuel economy-meanig the computer is saying to upshift for better fuel economy. Funny, I was in town, only driving around 30 mph.
If you're not hearing the fuel pump-for the first few seconds after turning the key to the on position-you might want to check your fuel pump relay. The wiring on mine had shrunk back and bare wires were touching one another-I fixed that and replaced the relay-cheap-about $12. then I cou8ld hear the fuel pump priming again.I'm about to replace the filter-when was the last time you replaced yours? Good Luck.
If you're not hearing the fuel pump-for the first few seconds after turning the key to the on position-you might want to check your fuel pump relay. The wiring on mine had shrunk back and bare wires were touching one another-I fixed that and replaced the relay-cheap-about $12. then I cou8ld hear the fuel pump priming again.I'm about to replace the filter-when was the last time you replaced yours? Good Luck.
Thread Starter
Instructor
Joined: Jun 2003
Posts: 126
Likes: 7
From: Markham Ontario
Rick,
Yes, sounds like a similar problem. Funny thing is that the car starts every time. This morning before I left for work, I fired it up and it ran and idled perfect. But again, I still am not hearing relay, but it starts.
If I can't hear the relay, should the car not start?? Strange. But good.
Dunno. Really don't want to take it in to have it diagnosed at something like $70/hr....but if I have to.....
Thanks.
DSSKing
=============
2003 Acura TL (Dec 2002)
2000 Pontiac Montana (wife) (Sept 2002)
1988 Corvette L98 Coupe (May 2003)
1957 Chevy Bel Air Sedan (Sept 2004)
Yes, sounds like a similar problem. Funny thing is that the car starts every time. This morning before I left for work, I fired it up and it ran and idled perfect. But again, I still am not hearing relay, but it starts.
If I can't hear the relay, should the car not start?? Strange. But good.
Dunno. Really don't want to take it in to have it diagnosed at something like $70/hr....but if I have to.....
Thanks.
DSSKing
=============
2003 Acura TL (Dec 2002)
2000 Pontiac Montana (wife) (Sept 2002)
1988 Corvette L98 Coupe (May 2003)
1957 Chevy Bel Air Sedan (Sept 2004)
Le Mans Master
Joined: Oct 2003
Posts: 6,130
Likes: 2
From: seattle WA
The fuel pump relay is located on the firewall, next to the wiper motor.
Mine did the same thing-most often it would start and run perfect, finally it wouldn't start at all.There were times I couldn't hear the pump either, but it still started. I suspect this was because the fuel line was holding pressure. But it finally died.
Mine did the same thing-most often it would start and run perfect, finally it wouldn't start at all.There were times I couldn't hear the pump either, but it still started. I suspect this was because the fuel line was holding pressure. But it finally died.
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Team Owner
Joined: Mar 2000
Posts: 83,383
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From: Boston, MA
Originally Posted by DSSKing
Okay, changed the relay and it still doesn't cycle......yet, the car starts.
Thread Starter
Instructor
Joined: Jun 2003
Posts: 126
Likes: 7
From: Markham Ontario
Yep, positive. Changed relays, interchanged with others (3) and still, nothing. I don't want to take the car out and get stuck somewhere.....
Assuming the relay is good (replacement), what's the next step? Aside from the relay, what's next? The Pump??
Assuming the relay is good (replacement), what's the next step? Aside from the relay, what's next? The Pump??
Team Owner
Joined: Mar 2000
Posts: 83,383
Likes: 87
From: Boston, MA
I wouldn't be so concerned with the cycling if it is starter and running. I'd be more concerned with the sputtering. Slap a fuel pressure gauge on taped to the windshield and take it for a ride. Have a passenger monitor the pressure in something like 2nd gear and ring it out to 5000 and see if it holds pressure or drops as the RPM increase.
Thread Starter
Instructor
Joined: Jun 2003
Posts: 126
Likes: 7
From: Markham Ontario
Okay, the car has been sitting for 24 hours. Just turned the key, again, no fuel pump noise, yet it started. I noticed there are relays below the filler nozzle at the rear of the car?? Could this be an issue?
Team Owner
Joined: Mar 2000
Posts: 83,383
Likes: 87
From: Boston, MA
Please for the love of god get off of the cyling issue and back to the sputtering. If your pump is weak it COULD be cycling, but you will not hear it. Slap a FP gauge on the windshield and go verify its putting out enough fuel at WOT.
Thread Starter
Instructor
Joined: Jun 2003
Posts: 126
Likes: 7
From: Markham Ontario
Thanks to Wheelman, Scorp508 and Rick..... Fuel pump was the problem. Took 30 minutes for the swap and she runs beautiful. Had it out twice since the swap in Thursday and have absolutely no problems. The car seems to run stronger ....
Thanks again.....hats off to this forum!!!
DSSKing
Thanks again.....hats off to this forum!!!
DSSKing